The Republic of Croatia has introduced reform of the judiciary over the past years to assess the constitutionality and legality of general acts. With the entry into force of the 2010 Administrative Disputes Act, the assessment of legality becomes the subject of an administrative dispute for which the High Court of Justice of the Republic of Croatia has jurisdiction. This delimits the competence to assess the legality of the general acts of the Constitutional Court of the Republic of Croatia and the High Administrative Court of the Republic of Croatia. The subject of research comes from the effects of a new model of controlling the legality of general acts, a comparison of the previous practice of assessing the legality and the practice that appears today in the legal order. The methods used for classifying, content analysis, deduction methods, induction methods, comparative methods, compilation methods and case study methods were used in this paper. By analyzing the subject of the research, and by concluding with the induction and deduction methodology, a general conclusion was made and the topics of the thesis work. The adoption of the Administrative Disputes Act positively influenced the legal order of the Republic of Croatia and contributed to the development of legislation.